Question 1

Which of the following is not a property of carbon?

Accepted Answer

A)  It can form single,double,and even triple bonds with itself.
B)  It can be built into rings and long chains.
C)  It constitutes the backbones of an incredible variety of molecules.
D)  All compounds made from carbon are soluble in water.
E)  All organic molecules contain carbon atoms. D

Question 2

Imagine that you were able to see a nucleotide under a very special microscope.As you scan the nucleotide you see a T nitrogen base.Without seeing any other part of the nucleotide you know that

Accepted Answer

A)  it is a DNA nucleotide.
B)  it is a RNA nucleotide.
C)  it is a either a DNA nucleotide or an RNA nucleotide.
D)  you will need to continue to scan for more clues,such as the type of sugar associated with it,to be able to determine which type of nucleotide it is. A

Question 3

The information storage molecules of cells are called

Accepted Answer

A)  fatty acids.
B)  membrane lipids.
C)  enzymes.
D)  hormones.
E)  nucleic acids. E

Question 4

Non-polarity and insolubility characterize biological compounds known as _______.

Accepted Answer

A)  carbohydrates
B)  lipids
C)  proteins
D)  nucleic acids

Question 5

Nucleic acids are created with

Accepted Answer

A)  phosphodiester bonds
B)  peptide bonds
C)  a phosphate and two fatty acids bonded to glycerol
D)  sugar polymers

Question 6

The simplest and the most common monosaccharide is a six-carbon sugar called

Accepted Answer

A)  galactose.
B)  lactose.
C)  cellulose.
D)  glucose.
E)  sucrosE.

Question 7

Which of the following macromolecules are characteristically water-insoluble?

Accepted Answer

A)  proteins
B)  nucleic acids
C)  carbohydrates
D)  lipids
E)  enzymes

Question 8

Lipids are the only class of macromolecules that contain

Accepted Answer

A)  amino acids.
B)  nucleic acids.
C)  fatty acids.
D)  phosphate groups.
E)  sugars.

Question 9

In _________ the average chain length of amylose is much greater and there are more branches than in plant starch.

Accepted Answer

A)  proteins
B)  cellulose
C)  glucose
D)  glycogen

Question 10

Alpha helix and beta pleated sheets are examples of which level of protein structure?

Accepted Answer

A)  zero order
B)  primary
C)  secondary
D)  tertiary
E)  quaternary

Question 11

Carbohydrates contain 4 calories per gram,proteins contain 4 calories per gram,and fats contain 9 calories per gram.There is a food that contains 108 calories per serving.There are 4 grams of carbohydrate,5 grams of protein,and 8 grams of fat in a serving.Which of the following represents the calories for fat?

Accepted Answer

A)  20
B)  16
C)  72
D)  18

Question 12

Cystic fibrosis (CF)is an inherited disorder that is caused by a mutation that prevents various ions from moving across cell membranes.Normally there are proteins that allow passage of the ions,but in CF these proteins seemed to be disabled.Researchers have found that one explanation of this has to do with

Accepted Answer

A)  the chaperone proteins are missing or are not functioning and,thus,the correct folding of the proteins are prevented from occurring.
B)  the proteins are denatured and as a result become disabled,which prevents the correct interface with the substrate,effectively blocking ion transfer.
C)  the chaperone proteins are bound with the ions at the cell membrane surface and cannot release to aid the unfolded proteins.
D)  the proteins are disabled because of the pH change at the cell membrane surface caused by the accumulated ions.
E)  the chaperone proteins and the proteins are unable to segregate themselves because of the lower pH environment produced by the ionic gradient created on the cell membranE.

Question 13

Carbohydrates are polymers formed of structural units called

Accepted Answer

A)  amino acids.
B)  fatty acids.
C)  nucleic acids.
D)  phosphate groups.
E)  monosaccharides.

Question 14

The nitrogen base not found in DNA is called

Accepted Answer

A)  adenine.
B)  cytosine.
C)  guanine.
D)  thymine.
E)  uracil.

Question 15

L-lysine is an essential amino acid and must be supplied in the diet.By comparison,the stereoisomer D-lysine is not biologically active.Why can your body only utilize one form?

Accepted Answer

A)  Since the L form and D form are enantiomers,they will bind together and inhibit utilization of the D form.
B)  Since the L form and D form are chiral molecules,they will bind together and inhibit utilization of the D form.
C)  Antibodies recognize the D form and destroy it before your body can use it for nutritional purposes.
D)  Enzymes can only recognize a single,specific stereoisomer.

Question 16

Four of the following five choices are functions of carbohydrates.Select the exception.

Accepted Answer

A)  Chitin is a carbohydrate that is used in insects and other arthropods in the structures of their exoskeletons.
B)  Starch is a carbohydrate that is used by some plants as a way to store glucose.
C)  Glycogen is a carbohydrate that is used by animals as a way to store glucose.
D)  Cellulose is a carbohydrate that serves a structural function in plants.
E)  Glucose is a carbohydrate that is utilized by all life forms in the construction of nucleotides.

Question 17

Three of the four macromolecules present in living systems are ________ which means they are built by linking together small,similar chemical monomers.

Accepted Answer

A)  polymers
B)  functional
C)  evolved
D)  carbon-based

Question 18

DNA,RNA,and ATP contain functional units known as

Accepted Answer

A)  peptides.
B)  enzymes.
C)  amino acids.
D)  nucleotides.
E)  fatty acids.

Question 19

You arrive late to a biological seminar.However,just as you enter the room,you hear the speaker referring to the "amino end" and the "carboxyl end" of a macromolecule.Immediately,you know that they are talking about a

Accepted Answer

A)  carbohydrate.
B)  protein.
C)  DNA.
D)  lipiD.

Question 20

Which of the following lipid classes is found in Chlorophyll,retina of the vertebrate eye,and synthetic rubber?

Accepted Answer

A)  phospholipid
B)  terpene
C)  steroid
D)  prostaglandin
E)  wax

Exam 3: The Chemical Building Blocks of Life